A volume slider to level out the music/in-game sounds ratio would be nice. After the 4th/5th attempt, I'm starting to depend on hearing the tell-tale banging of a zombie trying to get in. Sometimes the music overwrites that sound trigger and distracts the immersion. I really dig the music, I think it adds a lot. I love that it's not on a continuous loop. The music is definitely part of the brand now, but I'd like the option to mix it into the experience.